ProCGroups.FoxDifferential.Completed.DifferentialModule.TargetQuotient.MulProjection
The principal declarations in this module are:
primePowerCompletedGroupAlgebraFreeFoxDerivativeToCompletedTarget_mul_projectionThe finite-stage projection of the prime-power completed target derivative satisfies the Fox product rule.
Theorem
FoxDifferential.primePowerCompletedGroupAlgebraFreeFoxDerivativeToCompletedTarget_mul_projection
theorem primePowerCompletedGroupAlgebraFreeFoxDerivativeToCompletedTarget_mul_projection
[TopologicalSpace (FreeGroup X)] [IsTopologicalGroup (FreeGroup X)]
[DiscreteTopology (FreeGroup X)]
(N : Subgroup (FreeGroup X)) [N.Normal]
[TopologicalSpace (foxAlgebraicStageTargetQuotient (X := X) N)]
[IsTopologicalGroup (foxAlgebraicStageTargetQuotient (X := X) N)]
(hfinite : ∀ a : ℕ,
Finite (FreeGroup X ⧸
foxCommutatorPowerSubgroup (F := FreeGroup X) N (ℓ ^ a)))
(i : X) (x y : PrimePowerCompletedGroupAlgebra ℓ (FreeGroup X))
(j : PrimePowerCompletedGroupAlgebraIndex
(foxAlgebraicStageTargetQuotient (X := X) N)) :
primePowerCompletedGroupAlgebraProjection
(ℓ := ℓ) (G := foxAlgebraicStageTargetQuotient (X := X) N) j
(primePowerCompletedGroupAlgebraFreeFoxDerivativeToCompletedTarget
(ℓ := ℓ) (X := X) N hfinite i (x * y)) =
primePowerCompletedCoeffProjection (ℓ := ℓ) (G := FreeGroup X)
(j.1, foxAlgebraicStagePrimePowerSourceCompletedIndex
(ℓ := ℓ) (X := X) N hfinite j.1)
(primePowerCompletedGroupAlgebraAugmentation
(ℓ := ℓ) (G := FreeGroup X) y) •
primePowerCompletedGroupAlgebraProjection
(ℓ := ℓ) (G := foxAlgebraicStageTargetQuotient (X := X) N) j
(primePowerCompletedGroupAlgebraFreeFoxDerivativeToCompletedTarget
(ℓ := ℓ) (X := X) N hfinite i x) +
primePowerCompletedGroupAlgebraProjection
(ℓ := ℓ) (G := foxAlgebraicStageTargetQuotient (X := X) N) j
(primePowerCompletedGroupAlgebraMap
(ℓ := ℓ) (G := FreeGroup X)
(H := foxAlgebraicStageTargetQuotient (X := X) N)
(foxAlgebraicStageTargetQuotientContinuousMonoidHom (X := X) N) x) *
primePowerCompletedGroupAlgebraProjection
(ℓ := ℓ) (G := foxAlgebraicStageTargetQuotient (X := X) N) j
(primePowerCompletedGroupAlgebraFreeFoxDerivativeToCompletedTarget
(ℓ := ℓ) (X := X) N hfinite i y)The finite-stage projection of the prime-power completed target derivative satisfies the Fox product rule.
Show Lean proof
by
rw [primePowerCompletedGroupAlgebraFreeFoxDerivativeToCompletedTarget_projection,
primePowerCompletedGroupAlgebraProjection_mul]
change
modNCompletedGroupAlgebraStageMap (ℓ ^ j.1)
(foxAlgebraicStageTargetQuotient (X := X) N) j.2
(foxAlgebraicStageGroupAlgebraDerivative (X := X) N (ℓ ^ j.1) i
((show foxAlgebraicStageSourceGroupAlgebra (X := X) N (ℓ ^ j.1) from
primePowerCompletedGroupAlgebraProjection (ℓ := ℓ) (G := FreeGroup X)
(j.1, foxAlgebraicStagePrimePowerSourceCompletedIndex
(ℓ := ℓ) (X := X) N hfinite j.1) x) *
(show foxAlgebraicStageSourceGroupAlgebra (X := X) N (ℓ ^ j.1) from
primePowerCompletedGroupAlgebraProjection (ℓ := ℓ) (G := FreeGroup X)
(j.1, foxAlgebraicStagePrimePowerSourceCompletedIndex
(ℓ := ℓ) (X := X) N hfinite j.1) y))) =
_
rw [foxAlgebraicStageGroupAlgebraDerivative_mul]
rw [map_add, map_mul]
rw [show
modNCompletedGroupAlgebraStageMap (ℓ ^ j.1)
(foxAlgebraicStageTargetQuotient (X := X) N) j.2
(foxCommutatorPowerGroupAlgebraMap
(F := FreeGroup X) N (ℓ ^ j.1)
(primePowerCompletedGroupAlgebraProjection (ℓ := ℓ) (G := FreeGroup X)
(j.1, foxAlgebraicStagePrimePowerSourceCompletedIndex
(ℓ := ℓ) (X := X) N hfinite j.1) x)) =
primePowerCompletedGroupAlgebraProjection
(ℓ := ℓ) (G := foxAlgebraicStageTargetQuotient (X := X) N) j
(primePowerCompletedGroupAlgebraMap
(ℓ := ℓ) (G := FreeGroup X)
(H := foxAlgebraicStageTargetQuotient (X := X) N)
(foxAlgebraicStageTargetQuotientContinuousMonoidHom (X := X) N) x) by
rw [primePowerCompletedGAProj_map_targetQuotient_eq_freeDerivativeSource]]
rw [primePowerCompletedGroupAlgebraFreeFoxDerivativeToCompletedTarget_projection,
primePowerCompletedGroupAlgebraFreeFoxDerivativeToCompletedTarget_projection]
rw [foxCommutatorPowerSourceGroupAlgebraAugmentation_projection_eq_completed
(ℓ := ℓ) (X := X) N hfinite y j.1]
rw [Algebra.smul_def, map_mul, modNCompletedGroupAlgebraStageMap_algebraMap,
← Algebra.smul_def]